Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
6475812 | Fuel | 2017 | 7 Pages |
â¢The permittivity of diesel fuel and blends with biodiesel was determined at 100 kHz.â¢The measurement uncertainty was below 1%.â¢Linear dependences with temperature and composition were found.â¢Composition is estimated from permittivity and temperature measurements.â¢The RMS uncertainty of biodiesel content estimation is below 2.5%.
The relative permittivity of diesel fossil fuel and blends with biodiesel from soybean, in the full range from pure diesel to 100% biodiesel, was determined at temperatures between 298.0 K and 333.0 K (controlled within ±0.1 K), using an airtight cell. Measurements were made in the frequency range from 1 kHz to 100 kHz; this frequency range is suitable for the use of low-cost, portable equipment and also for the development of automotive sensors. The relative uncertainty of the measurements was below 1%.Experimental values of permittivity were satisfactorily fitted to a simple model as a function of temperature and composition. The RMS uncertainty of the fitting was 1.2%. The model parameters were determined from experimental results and verified by multiple regression analysis, with very good agreement.In addition, a model was proposed to estimate the composition of diesel/biodiesel blends from permittivity and temperature measurements. The parameters of the model were obtained by a multiple regression analysis; the RMS uncertainty of the composition estimation was below 2.5%.The results presented in this work describe accurately the dependence of the permittivity of diesel fuel with temperature and also validate and extend previously reported models for biodiesel-rich blends with diesel fossil fuel, allowing the estimation in the full composition range with good accuracy.